Indigo Dye 1876 – possible origins of locally HK posted indigo.

HF wrote this in response to a comment on the article below by Sally Trainor: Your comments made me dig out a book, Victoria Finlay, Colour: Travels Through the Paintbox, Sceptre, 2002, which is an extensive account of the history, origins and places of production of all the colours an artist would use.

And that got me thinking about the textile and garment industries in Hong Kong, what dyes they used and where they came from. Indigo must have been one…but what else?

If you have any knowledge on this or related subjects please write to me at indhhk(at)gmail.com

Hugh Farmer: A Brief Introduction to Indigo Dye and its Production in South and East Asia

HF: 23/1/14 Sally Trainor’s recent comment allows me to re-post an article I wrote in I think August 2013. It was a favourite subject of mine in what now seems like the early days of this group. The article had lots of lovely components. In HK colonial terms a rather distant history, an unusual subject and something of a mystery. Here’s the original article:-

Indigo dye is an organic compound with a distinctive blue colour. Historically it was a natural dye extracted from a variety of plants and was economically important worldwide because blue dyes were once rare. Nearly all indigo produced today, several thousand tons annually, is synthetic and is probably best known as the colour in blue jeans. It is claimed that natural indigo was used as far back as 5000 BC. The word is sometimes used to indicate the particular colour and a variety of plants, both temperate and tropical, have provided this throughout history. Elsewhere indigo is used to specifically highlight the tropical Indigofera tinctoria variety which was domesticated in India, the earliest major centre for its production and processing. The dye was exported from there to Europe during the Greco-Roman period probably by Arab merchants and initially as a luxury product. The same dye is found in the woad plant Isatis tinctoria, which for a lengthy period was used as the main source of blue dye in Europe until it was replaced by “true indigo” as these trade routes developed.

Indigofera tinctoria also known as True Indigo

The association of India with indigo is reflected in the Greek word for the ‘dye’, which was indikon (ινδικόν). The Romans used the term indicum, which passed into Italian and eventually into English as the word indigo. A common alternative used in relatively colder subtropical locations such as Japan’s Ryukyu Islands and Formosa (Taiwan) is Strobilanthes cusia. In Central and South America the two species Indigofera suffruticosa and Dyer’s Knotweed (Polygonum tinctorum) have been cultivated although the Indigofera species yield more dye.

Natural indigo has been grown in Africa, Indonesia, the USA, Central and South America.

In 1897, 19,000 tons of indigo were produced from plant sources. Largely due to advances in organic chemistry, production by natural sources dropped to 1,000 tons by 1914 and continued to contract. These advances can be traced to 1865 when the German chemist Adolf von Baeyer began working on the synthesis of indigo. It was not however until 1897 that two German companies devised a cheaper and purer synthetic substitute in quantities suitable for marketing.

As much as 20 tonnes of leaves are needed to produce just 45 kilos of pigment and unlike other natural dyes, indigo is not present in the plant. Only the chemical precursor of indigo is present, and the leaves need to be processed to produce the indigo powder.

The process of obtaining the dark blue dye liquor from Indigo plants started with fermentation in a tub filled with an alkali solution. The dye liquor would harden and be cut into hand-size chunks. Cases of these chunks were sold to Indigo dyers who would grind it to a powder. At this stage it was soluble in water. The mixture would be boiled, then cooled and stirred removing any extraneous materials like twigs that would affect the printing. Next the mixture was put into the vat with the cloth; copperas and lime were added, making the dye bath yellow in color.

After a time, the cloth also turned yellow. It wasn’t until it was lifted from the vat and oxygenation took effect (after about 12-15 minutes) that the cloth turned blue, and the indigo was insoluble again.

Now, to attempt to answer James Chan’s Queries and Answers question 8. Indigo in Hong Kong, asking where indigo sent by post from Hong Kong in 1876 originated from. I can find no record of indigo being produced in the territory itself.

Here are the three main suspects:

Formosa. (Taiwan) Here is a report from 1885. “Grass-cloth fibre and jute are… exported [from Formosa] in small quantities. The first is exported to China to be woven into summer grass-cloth. Manufactured grass-cloth and other cloths are sent to Formosa to be dyed with the fresh Formosan indigo, famed throughout China for its bright and durable tints. The northern districts produce indigo, which, packed in large tubs, is shipped in the liquid state, to Amoy [Xiamen] and Shanghai principally.” And perhaps to Hong Kong in hardened blocks?

Japan. In the 19th century Shikoku island, in particular the Awa region (present day Tokushima prefecture) became the centre of indigo production in the country due its rich soil, abundant water supply and beneficial climate. Before the development of synthetic indigo the region was one of the wealthiest in Japan as the country’s dominant area for indigo leaf production. The Ryukyu islands were another centre for indigo production in Japan.

India. The largest producer and exporter of indigo in the 19th century. The demand for indigo in the late 19th century is indicated by the fact that in 1897, about 7000 square kilometers in the country were dedicated to growing indigo plants. At its height, the industry employed about one million people there in either production or in preparation for transport to Europe. In 1895-1896 111,714 cwt (5,675 metric tons) were exported from Calcutta (Kolkata). The principal market was England from where it was re-shipped to other parts of the world. There was huge demand to supply the textile industries of the industrialised countries – or example the USA where more commercially valuable cotton had replaced indigo in the 18th century. In particular it was used to dye European military uniforms.

An Indigo factory, Bengal, India 1867

It is possible but unlikely that the indigo would have been shipped from India to Hong Kong and then back to Italy as mentioned in the China Mail 1st May 1876. Therefore Japan or Formosa would appear to be the most likely sources. However, it would be good to hear from anyone who could narrow the field further.

Indigo did not just pass through Hong Kong. Here is a very brief part of an oral history provided in 2010 by Lai Yiu Kai who in 1972 started working for the Kam Kee Fabric Company as a fabrics quality controller. “The fabric company decided on the dyeing and weaving plans according to the characteristics of different fabrics. In [the] case of denim, the yarn instead of the fabric was dyed. The first step was to import cotton yarn from the mainland…..The imported yarn was sent to a dyer in Kwai Chung. The dyer would dye it in indigo, only the warp not the woof. The dyed yarn was then sent to the weaver.” It would be interesting to learn more about it use in Hong Kong.http://www.hkmemory.hk/collections/oral_history/All_Items_OH/oha_32/records/index.html#p55764

2 Comments

A succinct article on the fascinating colour of indigo. Well done! When I think of the countries in Asia where I have travelled over the years the ubiquitous indigo and all its different shades springs immediately to mind.

Your comments made me dig out a book, Victoria Finlay, Colour: Travels Through the Paintbox, Sceptre, 2002, which is an extensive account of the history, origins and places of production of all the colours an artist would use.

And that got me thinking about the textile and garment industries in Hong Kong, what dyes they used and where they came from. Indigo must have been one…but what else?

If you have any knowledge on this or related subjects please write to me at indhhk(at)gmail.com